UC Irvine

A method for incorporating dynamic covalent bond into epoxy networks has been developed using a siloxane exchange pathway with the help of a fluoride catalyst, CsF. It has been demonstrated that the siloxane-based epoxy network containing catalytic amounts of CsF exhibits dynamic behavior, allowing for the exchange of cross-linked bonds within a useful temperature range of 160 °C to 200 °C. This pathway exhibits a lower activation energy and improved thermal stability compared to the same siloxane-based epoxy network catalyzed by 1,5,7-triazabicyclo [4.4.0] dec-5-ene (TBD) as an organic catalyst. Furthermore, the CsF-catalyzed polymer has been shown to maintain the same stress-relaxation rate and crosslinked density after being reprocessed up to five times.